Regulator resistance



April 1943- w. SCHONFELD REGULATOR RESISTANCE Filed Nov. 2, 1940 INVENTOB W/LH'ELM SCHONFELD BY 7 ATT oRNEY Patented Apr. 13, 1943 UNITED STATES PATENT OFFICE REGULATOR RESISTANCE Wilhelm Schfinfeld, Berlin, Germany; vested in.

the Alien Property Custodian Application November 2, 1940, Serial No. 364,022 In Germany September 19, 1939 1 Claim.

port for the resistance coat, possess adequate mechanical strength and also suflicient insulation power. The thermal inertia is but little raised by the insulation material inasmuch as their heat conducting power is so low that it is practically only the hydrogen which produces a cooling effect upon the large outer surface of the filament that determines the temperature of the iron. Disturbances due to dissimilar heat expansion values their production nor for their use and transporta- 10 of iron and quartz need not be feared since the tion. What should be kept in mind in this contenuous film of the iron readily adapts itself to nection is that where iron-hydrogen resistances the thermal expansion of the quartz.

are employed in practice the demands made re- The drawing, to an exaggerated scale, shows garding their rigidity and strength are mostly the cross-section of a resistance filament accordsevere. For instance, changes in their sag will 15 ing to the invention. The quartz filament I carappreciably affect the properties of the resistance.

Now, to make regulator tubes for currents as low as stated a thin filament of quartz or a similar material is used according to the invention, say, quartz glass. This quartz or the like filament is then coated, say, by a galvanizing process, with a film or coat of iron. The quartz filament could have a thickness of, say, 5 a (microns), while the thickness of the iron film may be of an order of 1 a (micron).

The stabilizing range of iron lies at temperatures ranging between grey and cherry redness, that is, around 700 degrees C. Inside this range the suggested insulators when serving as a supries the thin iron coat 2 applied thereon by a galvanic or electro-plating process.

I claim:

A resistance element for an iron-hydrogen current stabilizing device comprising a core composed of quartz glass whose mechanical strength and insulation power are not appreciably affected when it is raised to temperatures of around 700 C., and a comparatively thin coating of iron around at least a portion of the length of said core, said iron having an effective current stabilizing range when its temperature is around 700 C.

WILHELM scnoumn. 

